"Let no freedom be allowed to novelty, because it is not fitting that any addition should be made to antiquity. Let not the clear faith and belief of our forefathers be fouled by any muddy admixture."
-- Pope Sixtus III

Thursday, March 30, 2017

The victim lay across the doorway of a filthy Mount
Airy home, a 12-gauge shotgun blast through his chest. The suspect
had called in a confession, and the evidence was clear. But that day
in April 1999, police puzzled over dark stains on a wall far from the
man's body.

"It didn't make sense," said forensic
investigator Mitchell Dinterman. "These were all the way across
the room.

He noticed an open window. The stains, he realized,
came from flies.

Crime scene
investigators have long relied on their own judgment to distinguish
blood spatter from the look-alike stains left by flies that land on
the body and then on a spot nearby. Now a biology professor at Loyola
University Maryland is developing a spray that
removes the guesswork.

David Rivers has worked on and off for five years to
isolate an enzyme distinctive to the fly gut. He won a $154,521 grant
from the U.S. Department of Justice in December to complete
development of his spray over the next two years.

His research stretches the limits of traditional
forensic science — "Even the crime shows don't talk about it,"
he said — and it's a field best avoided by the squeamish: forensic
entomology, the study of bugs in deaths.

"It's unsettling to think flies are getting to a
body," he said. "When we're thinking about someone's loved
one, we don't want to think about that."

Rivers teaches the only college course on forensic
entomology in Maryland, he said. At his research lab, flesh flies and
hide beetles dine on cow livers in screened cages. A cow skull and
rat skeleton are picked clean. He urges visitors to remove their
sweaters or wool coats.

"Certain fabrics retain the smell of death,"
Rivers explained.

As a boy, Rivers kept fireflies in a mayonnaise jar
in his mother's refrigerator. He wanted to be a scientist when he
grew up, and planned to study genetics. But he found himself instead
as a research biologist, milking venom from tarantulas.

Today he studies the flies that feed on corpses.

Blowflies are common in Maryland, identifiable by
their metallic green or blue bellies, and able to sniff out death
from a mile away. A corpse dumped in summer attracts the flies within
five minutes, Rivers said. He sets up mock crime scenes around campus
with caged animal remains. And the flies start buzzing around him
when he's 10 feet out the door with the cages.

These flies grow two and three times bigger than
house flies but can crawl inside a car with its doors and windows
closed.

Rivers encountered
the flies in the early 1990s while consulting on a case as a graduate
student at Ohio
State University. An elderly woman had died
alone in her old Victorian home and the flies got in. The house was
cleaned and sold to a young couple who discovered thousands of flies
hidden in the air ducts. The sale was rescinded under Ohio's lemon
laws, Rivers said.

Also, they're slobs. Flies slurp and dribble and wear
their food. They spit up after eating or before they begin. Their
digestion can occur outside the body.

This makes for a gruesome mess, considering
blowflies' taste for bodily fluids. Mealtime may proceed like this:
Flies lap up blood, mix it with digestive juices and spit it out.
They wander off to wait out the digestion and return to sponge up
their meal — bon appetit.

Swarms can really muck up a crime scene.

"They leave these little marks and it resembles
a lot — quite a lot — like impact spatter," said Chief
Steven O'Dell, director of the Baltimore City police crime lab. "It
could lead you to a wrong conclusion, to decide a witness statement
is incorrect, or maybe an impact happened over here, or maybe there's
some other body that's missing …

"It confuses you," he said. "It can
slow the investigation down."

Investigators routinely measure the tiny tails of
blood spatter to calculate the angle and location of a violent blow.
This is called "directionality."

Flies leave nearly identical tails when buzzing
around and spitting up, which can further confound investigators.

"It creates these little streaks that look like
bloodstains that hit an object with some directionality," O'Dell
said.

Still, scenes disturbed by flies remain an uncommon
occurrence, mostly found in suburban and rural communities where
bodies may linger undiscovered. In Baltimore, shootings typically
happen on streets, and such evidence rarely factors into
investigations.

"We actually see it quite a bit down here,"
said Holly Latham, a forensic scientist with the Kansas Bureau of
Investigation, who has presented case studies on blood spatter during
annual meetings of forensic investigators with the International
Association for Identification.

Latham was unaware of Rivers' project.

"It does sound intriguing," she said.

A study published in November 2003 in the journal
Forensic Science International offered investigators tips for
distinguishing fly spots from blood spatter.

Tails of fly spots will point in random directions,
the study advised. Another clue: spots found in rooms without a body.
And flies will concentrate on lights, mirrors and windows.

The study presented a case from June 1997, in which
two men were found shot dead in a Nebraska apartment. Spray around
the apartment suggested a struggle, perhaps a robbery. But
investigators ruled out the stains as fly spots, changing their
theory to an execution.

"If you can
develop something that's more reliable, well, you don't make these
kinds of mistakes," said the study's co-author, Larry Barksdale,
a former police officer and forensic science professor at the
University
of Nebraska-Lincoln.

The first known case decided by forensic entomology
happened centuries ago in ancient China, according to Neal Haskell, a
prominent forensic entomologist. After a Chinese peasant was murdered
by someone wielding a hand sickle, the wise local magistrate ordered
villagers to lay down their sickles.

Blowflies alighted on the murderer's blade.

Haskell has testified in 32 states and recalls cases
where a victim's battered hands came from cockroaches feeding on dead
skin; in another, matted grass didn't signal a dragged body, but
maggots crawling off en masse.

He also has challenged evidence in court, testifying
that blood spatter was actually fly spots. A reliable spray would
prove invaluable to investigators, Haskell said.

"If this technique works," he said, "that
will help immensely."

Sometimes technicians can detect fly spots by shining
blue or purple light on stains and observing the specks through an
orange filter. It's an inexact method, but fly spots often glow. At
Loyola, Rivers has tested this method in his lab, finding true blood
stains also glow. Routine field tests for human blood fail to
distinguish fly spots as well.

"Every test that law enforcement has available
should test positive for human blood," Rivers said, "but
the reality is it winds up being derived from flies."

A student's casual question years ago — shouldn't
there be some way to tell? — launched his research to invent the
spray. He has isolated the flies' digestive enzyme and developed a
binding antibody. Tests of 10 common fly species revealed the enzyme,
but there remain dozens more to test over the next two years in his
lab. And that's just fine with the professor.

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About Me

First of all, the word is SEX, not GENDER. If you are ever tempted to use the word GENDER, don't. The word is SEX! SEX! SEX! SEX! For example: "My sex is male." is correct.
"My gender is male." means nothing. Look it up.
What kind of sick neo-Puritan nonsense is this? Idiot left-fascists, get your blood-soaked paws off the English language. Hence I am choosing "male" under protest.